#' LD data
#'
#' A dataset containing LD data
#' 
#' @docType data
#'
#' @usage data(LD.df.example)
#'
#' @format Dataframe of SNP linkage data, one row per SNP pair, with 5 columns (PLINK --r2 output format)
#' \describe{
#'  \item{BP_A}{Base pair position of the first variant in the LD pair. Data type: integer}
#'  \item{SNP_A}{Variant ID of the first variant in the LD pair. Data type: character
#'        Note: only variants that also appear in the GWAS.df SNP column will be used for LD analysis.}
#'  \item{BP_B}{Base pair position of the second variant in the LD pair. Data type:integer}
#'  \item{SNP_B}{Variant ID of the second variant in the LD pair. Data type: character
#'               Note: only SNPs that also appear in the GWAS.df SNP column will be used for LD analysis.}
#'  \item{R2}{Squared correlation measure of linkage between the two variants. Data type: numeric}
#' }
#'
"LD.df.example"